July 15, 1918 
Female Lepidoptera at Light Traps 
145 
represented by only 2 females, both spent. Of the remaining species of 
this family the percentage of gravid females varies from 3 7 P er cent in 
Meliana diffusa to 87 per cent in Folia renigera . Of the 424 females of 
Cirphis unipuncta dissected, 80 per cent were gravid, the eggs ranging 
in number from 107 to 773, all fully developed. 
Some explanation is required as to the method of arriving at the 
number of eggs accredited to a female moth where a footnote to a table 
reads “ Estimated.” The ovarian structure was dissected and spread for 
counting the eggs, adopting a unit of 25 eggs. The remaining ovarian 
material was divided into masses of the bulk of that containing 25 eggs. 
This method was frequently verified by actual counts and it is believed 
that the figures are dependable. Where no such reference appears, the 
actual count was made. In every case the stage of development was 
determined under the hand lens or binocular and indicated in Table III 
by “D” for “developed” and by “S” for “‘immature.” 
Any data as to the relative proportions of male and female Eepidoptera 
taken at a light trap have an added value when considered in connection 
with information bearing on these relations of the sexes in nature. For 
this reason the writer has endeavored to get together all facts to be had 
from available sources, and brief notes on the subject are cited here 
under the name of the species concerned. 
EUPROCTIS CHRYSORRHOEA EINNAEUS (j, p. 47~4 8 ) 1 
Concerning the brown-tail moth Fernald and Kirkland write as follows: 
In July, 1897, a quantity of cocoons and pupae was gathered and placed in a large 
glass-covered box, the moths being removed as they emerged. The following . . . 
shows the relative proportion of the sexes: Males, 399; females, 451. 
EEASMOPAEPUS EIGNOSEEEUS ZEEEER (lO, p. 20 ) 
Records obtained at Columbia, S. C., in 1915* From 56 pupae there 
emerged 23 males and 33 females. 
PHTHORIMAEA OPERCUEEEEA ZEEEER (4> P- 2 4) 
Graf records the following data with regard to the prooortion of sexes 
of the potato-tuber moth: 
The proportion of the sexes during the year remains very nearly constant and almost 
equal. Pupae selected at random at various times of the year gave the results shown 
in Table 3. (327 males, 284 females.) 
CRAMBUS HORTUEEEUS HTJEBNER ( I$, p . 8 ) 
With regard to the cranberry girdler, Scammell records the following 
data: 
In the early summer the males and females appear to be about equal in number; 
for example, on June n, 24 moths were collected, of which 12 were males and 12 
females. In late summer, however, the males are far in excess of the females, as 
shown by the following collections: Thirteen moths taken July 27 consisted of 11 
males and 2 females, while of 23 moths collected August 10 only 5 were females. 
Reference is made by number (italic) to “ Literature cited,” p. 148-149- 
